In the field of coatings, and in particular in the field of water-based coatings such as in printing inks and the like, wherein the coatings employ water dispersible polyester material as the ink varnish or binder, with or without colorants, problems associated with viscosity are commonly encountered and affect formulation and preparation of the coating compositions, their use, and the coated product appearance. For example, in the manufacture and use of conventional water-based, polyester containing printing inks, one is confronted in many instances with such problems as: limited viscosity range obtainable with such inks; substantial changes in viscosity of the ink compositions, e.g., during processing, particularly during operations wherein heating and/or shearing occurs, including printing, in particular, when thixotropic phenomena are present which reduce the shear viscosity of the polymer dispersion to a point where proper dispersal of the desired amounts of colorant therein by typical mixing apparatus becomes virtually impossible in that adequate shear is not developed to separate the pigment agglomerate; non-linear and unpredictable viscosity changes of the aqueous ink compositions with respect to polyester concentration; unpredictable build in viscosity of the ink compositions with time; difficulty in developing full pigment color during processing, as in milling operations wherein adequate viscosities of the compositions have not been achieved; and hazing and diminished gloss of the dried films such as occurs with conventional viscosity modifiers.